Diesel engine emissions

This introductory lecture provides an overview of emissions produced by diesel engines and the fundamental aftertreatment methods used to mitigate these pollutants. Students will be introduced to the types of emissions commonly associated with diesel engines—such as nitrogen oxides (NOx), particulate matter (PM), hydrocarbons (HC), and carbon monoxide (CO)—along with a high-level understanding of their environmental and health impacts.

The session will briefly introduce the core aftertreatment techniques, including Diesel Particulate Filters (DPF), Selective Catalytic Reduction (SCR), and Diesel Oxidation Catalysts (DOC), highlighting their roles in reducing specific pollutants. This lecture sets the stage for a deeper exploration in subsequent sessions, where we will dive into each emission type and aftertreatment technology in detail.

This lecture provides an in-depth look at particulate matter (PM) emissions produced by diesel engines, examining how PM forms during combustion and its significant impacts on health and the environment. Students will explore the composition of particulate matter, including soot, metallic ash, and other components, and learn about the different sizes of PM, such as PM10 and PM2.5, which can penetrate deeply into the respiratory system.

The lecture will cover the main factors that influence PM formation in diesel engines and how engine design and fuel characteristics impact PM levels. We will also introduce key methods for measuring particulate matter and briefly discuss control strategies, setting the stage for the following sessions on PM reduction techniques like Diesel Particulate Filters (DPF). By the end of this lecture, students will have a clear understanding of what particulate matter is, why it’s a concern, and the fundamentals of managing PM emissions.

In this lecture, students will explore nitrogen oxides (NOx) emissions—one of the most challenging pollutants to control in diesel engines. The session will cover the formation of NOx during combustion, focusing on the high temperatures and pressures in diesel engines that facilitate the reaction between nitrogen and oxygen.

We will examine the environmental and health impacts of NOx emissions, including their role in smog formation, acid rain, and respiratory issues. Key factors affecting NOx production, such as combustion temperature, air-fuel ratio, and engine load, will be discussed.

This lecture also provides an introduction to the main NOx control strategies, including in-cylinder techniques and aftertreatment methods such as Exhaust Gas Recirculation (EGR) and Selective Catalytic Reduction (SCR). By the end of the session, students will have a foundational understanding of NOx formation, its implications, and an overview of the technologies used to reduce NOx in diesel engines, setting up more detailed discussions in future lectures.

This lecture introduces Diesel Particulate Filters (DPF), a critical aftertreatment technology used to reduce particulate matter (PM) emissions in diesel engines. Students will learn how DPFs capture and filter out soot and other particulate matter from exhaust gases, significantly lowering the PM emissions released into the atmosphere.

The session covers the structure and operation of DPFs, including their filtration mechanisms, such as wall-flow designs, and the materials commonly used in DPF construction. Additionally, students will explore the regeneration processes, both passive and active, required to clean the filter and prevent clogging, along with challenges and maintenance considerations associated with DPFs.

By the end of the lecture, students will understand how DPFs work, their role in meeting emissions standards, and the operational practices required to maintain efficient filter performance. This knowledge will provide a practical foundation for managing PM emissions in diesel engines.

In this lecture, we will delve into the role and functioning of the Oxidation Catalyst in reducing harmful emissions from diesel engines. The oxidation catalyst is a key component in the exhaust after-treatment system, designed to reduce carbon monoxide (CO), hydrocarbons (HC), and, to some extent, particulate matter (PM) by promoting chemical reactions that convert these pollutants into less harmful substances.

Exhaust Gas Recirculation (EGR) is a widely used emission control technology in diesel (and gasoline) engines, designed to reduce the formation of nitrogen oxides (NOx), which are harmful pollutants. NOx is a significant contributor to air pollution, smog, and acid rain, and EGR helps to mitigate these impacts by reducing the combustion temperatures within the engine.

In this lecture, we will explore Selective Catalytic Reduction (SCR), a highly effective after-treatment technology used in diesel engines to significantly reduce nitrogen oxide (NOx) emissions. SCR is a critical component in meeting stringent environmental regulations, such as those set by the EPA and Euro standards, and is commonly found in modern diesel vehicles, trucks, and industrial engines.

By the end of the course, you will have a solid understanding of:

Diesel engine emissions and their impact on the environment

Emission reduction technologies and their effectiveness

Current and upcoming regulations governing diesel emissions

The future of diesel engines in a rapidly changing energy landscape

Whether you're a professional in the automotive or environmental sectors, or just someone passionate about reducing emissions and improving air quality, this course offers the knowledge and tools to navigate the complex world of diesel emissions management